Blast cupola-furnace



(No Model.) 2 Sheets-Sheet 1.

E. P. EURIOH.

BLAST-GUPOLA FURNACE.

No. 424,104. Patented Mar. 25, 1890.

ma mum." I I I Wd JIwm -o: MM 7 flW (No Model.) 2 SheetsShet 2.

E. F. EURIGH. BLAST OUPOLA FURNACE.

N0. 424;104. Patented Mar. 25, 1890.

UNITED STATES PATENT OFFICE.

ERNST F. EURICH, OF AURORA, ILLINOIS.

BLAST CU POLA-FU RNACE.

SPECIFICATION forming part of Letters Patent No. 424,104, dated March 25, 1890.

Application filed August 19, 1889. Serial No. 321,229. (No model.)

and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to lettersof reference marked thereon, which form a part of this specification.

This invention relates more particularly to an improvement in fore-hearths for blast cupola furnaces for smelting lead, copper, nickel, silver, and gold ores.

The most general use for the improvement will probably be in the smelting of lead ore.

In its use in the smelting of lead ore the improvement is designed to facilitate the separation of the lead or lead bullion and the slag and matte and similar products.

In smelting lead ores there is generally produced, besides the lead or lead bullion, varying quantities of matte or slag. These settle in the hearth of the crucible or furnace, where they separate more or less, according to their specific gravities, the lead or lead bullion going to the bottom, the matte lying upon the lead, and the slag lying upon the matte. This separation is effected to the fullest extent when the molten mass is least agitated. The molten mass in the hearth of the furnace is constantly agitated and disturbed by the descent of melted material from above; hence the separation of the matte and slag by gravity is effected to such a limited extent as to make their separate withdrawal impracticable. Hence, in the practice of today, these two materials are drawn as a mixture from the same tap hole, and thereafter separated by additional processes. It is apparent, then, that there is a necessity for placing the molten ore into a non-agitated condition in order that its components may separate by the action of gravity. For this purpose I have provided afore hearth which communicates freely with the main hearth or crucible, and in which the molten ore is not disturbed or agitated by melted material descending into it. Provision is made for separately drawing the matte and slag from the fore-hearth after they have separated. All the portions of the fore-hearth which are subjected to the destructive action of the molten material are formed of or protected by water-jackets, as will be hereinafter described. This fore-hearth is virtually of the nature of a trap, into which the molten products are allowed to move, and wherein they are guarded from the action of the material descending into the hearth or crucible.

In the accompanying drawings, Figure 1 is a front elevation of the lower portion of a furnace embodying my improvement. Fig. 2 is a vertical central section in the line w a; of Fig. 1. Fig. 3 is a horizontal section in line y y of Fig. 1. Fig. l is a vertical section in line .2 .2 of Fig. 3.

A is the hearth or crucible, the main portion of which is built of firebrick in the usual manner,.and is surmounted above by the ordinary' form of shaft B, extending to any desired height, which shaft is provided around its base with water-jackets B, having tuyeres 0r tuyere-openings CJ The front wall of the hearth A (see Fig. 2) is cut away sufficiently to leave a lateral opening to a chamber A outside of the said wall of the furnace. These water-j aokets are arranged to have water circulate through them in the usual manner. The water-jacket adjacent to the chamber A may be similar to the rest, or it may be a distinct section B capable of being removed and replaced when injured by the molten material. Said section may or may not extend below the remainder of the water-jackets. All that is essential is that it extend downward sufficiently to dip into the molten material and. seal the upper portion of the chamber A from the hearth A. The bottom of the chamber A is lower than the margin of the hearth A is at other portions of its circumference; but the bottom of the chamber A is higher than the bottom of the hearth A. The front or outer Wall of the chamber A is a waterjacket D, having water circulating through it, and resting against the fire brick of the hearth A and rising some distance above the lower edge of the adjacent portion of the water-jacket B or its equivalent. From the top of said water-jacket D a heat-resisting plate extei'idshorizontally over the chamber A and against the water-jaeket B An opening D extends through the water-jacket D in a horizontal line, passing a little above the lower edge of the adjacent portion of the waterjacket B and on the outside said opening is provided with a spout D Alittle below the level of the adjacent portion of the waterjacket B and at one side of the opening Dis a similar opening D, which is provided with a spout D.

The operation of the apparatus is as follows: The shaft B is charged and the smelting conducted in the usual manner. The ore on melting settles into the hearth or crucible A until the latter is filled to nearly the height of the lower edge of the water jacket B Then it extends over beneath the portion of the water-jacket adjacent to the chamber or fore-hearth A into said chamber, and thereafter it stands at the same level in the forehearth and in the hearth, the water-jacket B forming a division between the upper portion of the molten mass in each hearth. The portion of the molten material within the fore hearth is almost entirely isolated or sealed away from the hearth, and is not disturbed by the settling of the ore in and over the hearth. It can therefore respond to the action of gravity and separate into layers, the lead going to the bottom, the slag to the top, and the matte forming an intermediate stratum substantially distinct from the lead and the slag. The opening D is for the withdrawal of the slag as it rises to the surface of the mass of molten material, and the opening D is at a sufficiently lower level to stand opposite the stratum of matte, so that the latter may be withdrawn when desired. \Vhen the slag and matte are withdrawn, the adjacent water-jacket B prevents the flow from the surface of the molten mass in the hearth laterally into the chamber A. The only mode by which the molten material may pass from the hearth A into the fore-hearth A is by a quiet lateral movement below its surface. Thus it will be seen that the molten material within the fore-hearth is constantly quiet, so that its heavier parts are free to descend and its lighter parts free to rise. It is to be noted that during the course of this operation the walls formed by the water-jackets B and I) are exposed to the destructive action of the molten material. These walls would soon be destroyed if they were not formed of water-jackets. This will be apparent to persons experienced in the art and may be proven by test. If the front wall of the fore-hearth A were constructed of anything else than a water-jacket, the portions around the openings l') and D would soon be destroyed.

As already hereinbefore stated, the material in the fore-hearth separates into layers, the lead going to the bottom-that is, the bottom of the fore-heartl'i. Since the bottom of the fore-hearth is higher than the bottom of the hearth, the lead will, after descending to the bottom of the fore-hearth, respond further to gravity and descend laterally into the bottom of the hearth, whence it is withdrawn through the opening F into the lead-- well 1 From the well the lead is ladled in the wellknown manner. As fast as lead is withdrawn through the opening F, more room is made for clear molten lead to descend from above. Since the hearth is deeper than the fore-hearth, a large quantity of the molten ore is contained therein and exposed to the heat of the fire within the eupola above, so that the same does not chill before ladling.

It is to be noted that in the treatment of some ores speiss may be formed in lieu of or together with matte. When this occurs, the speiss is to be withdrawn with or in place of the matte and is to be regarded in connection with this apparatus as the equivalent of the matte. It is to be noted, further, that in my improved apparatus the necessity for the water-jacket is greater at the front of the base of the shaft than elsewhere, and that it is possible to operate my improved apparatus omitting the water-jacket at the sides and end of the base of the shaft. It is also to be noted that the walls of the base of the shaft 5 may be cooled by causing water to flow over or be sprayed against their outer faces instead of being made to circulate through them. This mode of cooling such walls is well known to this art, and I deem it unnecessary to illus- 10o tratc the same in the drawings.

I claim as my invention-- 1. In a blast cupola-furnace, the combination of the hearth or crucible A, having atits bottom an outlet 1*, a shaft 13, suri'nounting said hearth and having a water-jacket atits base, and a lateral chamber or fore-hearth A, communicating with the hearth A, and having a higher bottom than thelatter, and having a slag-outlet above the level of the lower face of the adjacent portion of the waterjaeket extending around the shaft B, substantially as shown, and for the purposes set forth.

:3. In a blast cupola-furnace, the combination of the hearth or crucible A, having at its bottom an outlet 1 a shaft 13, surmounting said. hearth and having a water-jacket extending around its base, and a lateral chamber or fore-hearth A, communicating with the hearth A, and'having a higher bottom than the latter, and having a slag-outlet above the level of the lower face of the adjacent por tion of the water-jacket extending around the shaft 1- substantially as shown, and for the purposes set forth.

3. In a blast cupola-furnaee, the combination of the hearth or crucible A, a shaft B, surmounting said hearth andhaving awaterjacket around its base, and a lateral chamber or fore-hearth A, communicating directly with the hearth A and separated therefrom only by said water-jacket, and having a water-jacket as its outer wall, and-a slag-out IIO let extending through said Water-jacket'above the level of the lower face of the adjacent portion of the water-jacket extending around the shaft B, substantially as shown, and for the purposes set forth.

4. In a blast cupola-furnace, the combination of the hearth or crucible A,having at its bottom an outlet F, a shaft B, surmounting said hearth and having awater-jacket around its base, and a lateral chamber or fore-hearth A,'communicating with the hearth A, and having a higher bottom than the latter, and

having a slag-outlet above the level of the,

lower face of the adjacent portion of the water-jacket extending around the shaft B, and having a matte-outlet a little below said slag-outlet, substantially as shown, and for the purposes set forth.

5. In a blast cupola-furnace, the combination of the hearth or crucible A, a shaft B, surmounting said hearth and having a waterjacket around its base, and a lateral chamber or fore-hearth A, communicating directly with the hearth A and separated therefrom only by said water-jacket, and having a water-jacket as its outer wall, and a slag-outlet extending through said water-jacket above the level of the lower face of the adjacent portion of the water-jacket extending around the shaft B, and having a matte-outlet a little below the slag-outlet, substantially as shown, and for the purposes set forth.

' 6. 111 a blast cupola-furnace, the combination of the hearth or crucible A, a shaft B, surmountin g said hearth and having a waterjacket around its base, the front lower section of which is removable, and a lateral chamber or fore-hearth A, communicating with the hearth A at its front, and having a slag-outlet above the level of the lower face of said removable section of the water-jacket, substantially as shown, and for the purposes set forth.

7. In a blast cupola-furnace, the co1nbina section at its front, and a lateral chamber or fore-hearthA', communicating with the hearth A at its front, and having a water-jacket as its outer wall, and a slag-outlet extending through said water-jacket above the level of the lower face of said removable section of the Water-jacket, substantially as shown, and for the purposes set forth.

,8. In a blast cupola-furnace, the combination of the hearth or crucible A, a shaft B, sin-mounting said hearth and having a waterjacket around its base, with a removable section at its front, and a lateral chamber or forehearth A, communicating with the hearthA at its front, and having a slag-outlet above the level of the lower face of said removable section of the water-jacket, and having a matteoutlet a little below said slag-outlet, substantially as shown, and for the purposes set forth.

9. In a blast cupola-fnrnace, the combination of the hearth A, a shaft B, surmounting said hearth and having a water-jacket around its base, with a removable section at its front, and a lateral chamber or fore-hearth A, communicating with the hearth A at its front, and having a water-jacket as its outer Wall, and a slag -outlet extending through said waterjacket above the level of the lower face of said removable section of the water-jacket, and having a matte-outlet a little below said slag-outlet, substantially as shown, and for the purposes set forth.

In testimony whereof I aflix my signature, in presence of two witnesses, this 12th day of Au- Witnesses:

AMBROSE RIsnoN, CYRUS KEHR. 

